1. Field of the Invention
The present invention relates to an optical write/read device capable of corresponding to an optical card or an optical disc and an information recording medium adapted for use in the optical write/read device.
2. Description of the Related Art
Recently, a medium for recording information therein using light represented by an optical card or optical disk has been noticed. An optical write/read device for writing information in and/or reading information from such medium comprises an optical head for use in writing/reading information and a moving mechanism for moving the optical head to a given position. There are various types of optical head such as a read-only type, a write-once type, an erasable magnet-optical type, wherein any type of the optical head includes fundamentally a light source, lenses and an optical detector (detector optical system).
However, the prior art optical write/read device has such an arrangement that an optical head having a single light source is moved at high speed by a moving mechanism along a plurality of tracks of an information recording medium, which are arranged in a width direction of the same medium, so as to record information in or read information from the medium. Accordingly, there have been needed (a) a complex detector optical system, and (b) a moving mechanism capable of moving an optical head in full width of the medium and also moving the optical head precisely along a desired track of the medium by way of a feedback control of the detector optical system, so that the optical head can be moved precisely along the desired track of the medium. Further, in the prior art optical write/read device, a recording optical system and a reading optical system must be individually provided. Accordingly, the optical write/read device has been complex and high-priced.